mine are the same age difference. we got the 16 month old a doll with stroller and feeding accessories--she got so attached to that baby and mimicked mommy with the real baby--even breastfeeding! She did run over baby sister's head with the stroller once, but I guess baby just learned to be tough! (*smiles*)
We went out of our way to give both kids lots of loves and cuddles... I probably had one kid or the other on my hip 90% of the time. We got a good double stroller and went for walks whenever we could--living in San Diego, fresh air was valued to break up the insanity inside the house.
It was hard, but very do-able, just keep trying different things suggested below and try to keep routines. I had grandparents close, so the 16 month old would go there on a regular schedule. That was HUGE help for me. Talking to my moms for tips and advice and just to vent was important too. I fought depression myself, so the family support was good. Don't be afraid to ask for help or tell people what type of help you can use if they offer.
we are big on sleeping through the night at our house, so we worked hard to encourage that with kids in their own rooms and only night feeding when baby is hungry--and transitioning after a few months to non-boob comforts at night so we could all be more rested and happy during the day.
(this is some time away, but potty training for #1 didn't happen till BFing was minimal b/c I wouldn't be able to help her if I have a baby attached to my chest!)
It'll start to feel like you have twins sometimes. Everything takes longer to do--grocery shopping, getting dressed in the morning...so plan ahead, allow extra time, don't over-schedule, and keep spare diapers in the car at all times (you are so busy now, you might forget to pack them, so this way you will always be ready).
There are lots of challenges at these ages, but benefits too. You can do it!
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and we read books on the couch with #1 while BFing #2.