Im not sure what to put on my registry! I have crib, etc. But what are the absolute most useful things for baby? I know there's tons of new baby products and helpful knick knacks. what are some of the best you had or wish you had?? Also, what are the absolute comfiest car seats for baby that aren't too heavy for mom? I have a heart condition and other health issues, so the lighter, the better. But I want baby to be comfy! some car seats feel really hard.