Almost 7 Mo Baby Suddenly Fighting All Naps & Sleep - Forgot How to Self Soothe?

He is just changing developmentally.
6 months old was also a growth-spurt... and also in terms of hitting milestones/teething/changing cognition/changing motor skills etc.
So ALL of these things, tweaks a baby and their sleep.
And ALL of these things, can and do occur in a baby all at the SAME time.
Normal.
Not easy for baby either.

Sleep in a baby is never finite or static.
It changes.
I do not know, of any child/Preteen/Teen/Adult/College Kid/Elderly person that has slept the SAME way they did as a baby.

Also, if he needs to feed, then feed on-demand.
Especially at growth-spurts.
Their intake needs to keep up with them.
Babies also do what is called 'cluster feeding'. Which means, they will feed even every single hour. Regardless of what time it is.
Thus, feeding on-demand is important.
A Hungry baby, cannot sleep.

Also, if a baby is over-tired or over-stimulated, they cannot sleep, nor fall asleep well.
Again, their changing cognition.

Over-tired babies/kids... actually cannot fall asleep well, wake more, and do not get a good sleep.
THUS, do not take away naps or sleep. It will make things worse.

Also yes, babbling. They do this anytime.
AND separation-anxiety crops up from about this age. It did with my kids.
Normal.

If he is teething, this will tweak their sleep.
Too.

Get the book "What To Expect The First Year."

I know most have said this is developmental; but I think if you really look at when it started you may see it is having the company that is affecting him. I know my kids react a lot when we have people visit, whether they are more tired or more 'wound up'. At 7mos it is always hard to really tell, as their sleep changes so much over the first year. I would try having some real down time that is calm and maybe make sure he can play by himself a few times a day without the gparents around. Just see if that helps for a day or two. My parents were receptive to things like this b/c they could see how much our kids needed their sleep. (and they like a break too!) Good luck!

Another possiblity is that he's achieved object permanance - meaning he understands that something or someone still exists even when they are out of sight. This milestone happens between 6-9 months and coincides with stranger awareness/fear. Before object permanance my daughter slept like a dream - all night long without a peep from 4 weeks old on. Once she turned 6 months it was all over! She KNEW mommy was in the other room and she didn't like it, she wanted me to be with her at all times! We then started co sleeping at night and I wore her in a sling while I puttered around the kitchen to put her to sleep for naps. Putting her in her crib was just a nightmare, and not a fight I was willing to fight (plus I knew I wouldn't win it, as my husband and I are not cry it out-ers). This may not be the solution for you, lots of people just can't sleep with their babies (not that I got all that much sleep, but it was better than the torment of hearing her cry!) Beware though, if you start co-sleeping or continue with the rocking it will likely go on for a long time (she's two and a half and I still sleep with her for half the night), until your son grows out of it (usually around age 3ish) or until you do another round of sleep training. Follow your gut, he may just be sick or ready to hit a new milestone like crawling, or needing extra cuddles to figure out the craziness of having visitors.

Looking back on when my kids were that young (now 3 and 1.5); my instincts were usually right on. It is likely all the reasons you think. I want to encourage you to remain consistent as much as is possible. Things change pretty regularly because of developmental stages, new discoveries and life circumstances make a difference too. Make special efforts to help him have some quite time.
Both of my kids had a difficult time winding down at the end of the day. You may not swaddle him anymore, but when you're holding him to go to sleep, you can wrap him in a blanket and hold him close, talk or sing quietly to him until he starts to relax.
The only think I'd ask you to reconsider is if teething is a factor. Sometimes more than one comes in at a time and you might not know about it until they actually break through. If he's in pain, some pain medicine might work wonders.

I think this is just a phase because my 7 month old daughter is doing the same thing right now we just spent an hour trying to get her to sleep and she will most likely be up again in a few hours to do it all again. We can't even rock her to sleep we just have to let her be until she is to sleepy to fight it. Good luck with your little one :)

I wonder if he is starting to crawl? (On all fours, rocking back and forth, or rolling, or sitting and "scootching" along) I noticed that whenever my girls hit any kind of milestone like that, they wanted to practice and practice, to the exclusion of all else. I would keep putting him down at his regular times for nap and bedtime. I would not get into the habit of rocking him to sleep. If he cries a little bit, it's not the end of the world. Babies like predictable routines, and he will be comforted by his routine even if he makes a fuss because he doesn't feel like sleeping at first. Also, over-stimulation is a possibility, but grandma and grandpa won't be there forever. Let them hold him to their hearts' content, but stick to the routine your son is used to in terms of sleeping and eating. Babies are really pretty adaptable little creatures as long as they have some form of stability to depend upon.

He is also at the age where he is starting to notice that he is a separate person from you. I know it sounds weird, but tiny babies perceive themselves as an extension of their caregivers. When they become more mobile, they realize that they are separate from you, and it scares them when you leave the room. You might try singing or talking to him when you're out of the room so he knows you haven't fallen off the face of the earth (how would he know where you are? his experience is very limited, really).