Your 6.5 month old did not "stop napping." He is just undergoing many changes now. This is totally normal. YES, he still needs to nap. Even 2 year olds still need a nap.
This is the age which is a "growth spurt" time... which means the get hungrier, need more intake because they are growing, AND need to feed more often.
(2) this is ALSO a time when they are changing a LOT developmentally, physically and cognitively AND emotionally.
(3) This is ALSO a time where they get "separation anxiety." Keep in mind, that "separation anxiety" fluctuates... meaning, it will come and go, at different ages & phases...throughout childhood. It is not something that just "appears" and then goes away. EACH age brings a different "version" of separation anxiety. SO...even when they are supposed to be sleeping... they will "miss" you and want to be close and see you. This happened with BOTH my kids too, at this age. And at other ages. Per my Pediatrician, this is common and happens.
(4) This is ALSO the age, where their motor skills are changing... they are about to crawl or are already... they are sitting up, they are rolling, they are beginning solids, etc. These are MANY changes going on with them at THE SAME TIME. THIS puts a kink into their adjustment... and in their "normal" patterns of sleep. This is normal. It is a phase... it will pass..
(5) you just need to ride it out. It's a phase. Yes, it's tiring for the Parent... BUT it is ALSO not easy for them... they are the one's changing/growing/getting hungrier etc. So, keep that in mind.
It's all about ages and stages and phases. More will come up.
Yes, it affects their sleep and naps. Just keep CONSISTENT... and KEEP to your routine. Make sure he is NOT over-tired, because over-tired babies/kids actually do NOT sleep very well, and it makes them have a hard time sleeping, and it makes them get up more.
(6) Sleep Patterns CHANGE in all babies/kids. It fluctuates per their development/age/intake etc. Even teenagers have fluctuating sleep habits. It will not just be static. It changes THROUGHOUT childhood. This is normal. Even adults do not sleep the same every night, nor do we sleep the same since we were babies, right? Well, babies are not exempt either. Sure, but having a routine and proper bedtime/nap times/sleep routines are important... so still instill that. It is important... sleep for anyone, is beneficial for development.
(7) Your baby may just be hungry... are you still feeding him on demand? He is growing... and as they grow they need to feed more... it is proportional to their changing development and bodies. Feed him, even if it is waking during the night.
Many times, a baby has a hard time sleeping because they are hungry, but are not being fed or not fed enough. I only say this because I have seen MANY MANY friends who had babies which were fussy and not sleeping well.... then, they found out that their babies were not getting enough intake.. .so they were basically always starving/hungry and never satisfied. The Doctors told them to feed on demand....and in 2 of my friends, the Moms were actually not producing enough milk... once their problem was solved and their babies were getting more intake... voila! Their babies started to be less fussy AND slept/napped better, and was all around more happy.
But, I can almost guarantee, that your baby is probably going through normal growth spurt and growth hunger... and he's changing. At this age, it is a "milestone" age, and they will develop in great leaps at this age. All these changes at the SAME time, causes hiccups in their normal pattern. It will occur again at any growth spurt period and milestone phase.
Just some ideas... all the best,
Susan