Love So Life is one of my favorites that has adorable kids in it.
Aka Chan to Boku - a classic
Aishiteruze Baby - highschool romance
Corseltel no Ryuujitsushi - life of 7 dragon toddlers and their babysitter. very cute XD http://www.mangago.me/read-manga/corseltel_no_ryujitsushi/
it seems Aishiteruze Baby is not available on mangago. so here's a link http://mangafox.me/manga/aishiteruze_baby/
Corseltel also very hard to read on mangago. the manga page is too small and looks bad, so here... http://mangafox.me/manga/corseltel_no_ryuujitsushi/v01/c001/1.html
Is there any manga that base kids in it like gakuen babysitters