hmmm ... in some ankos/stories babies and ko-yuu were kept warm inside father Marisa's Hat because carrying them inside mother Reimu's mouth infer the risk of melting. Not to mention swallowing.
I think for typical average/nice wild/stray yukkuri family, being carried is only for the youngest children, or the babies. When they are big enough (usually they have little sisters), they would walk on their own. They only ride on their parents when they're really tired. If they're big enough to have second set of sisters, they would help carry their younger sisters too, helping their parents.
Yu...OX ParkLittle one has said that lots already, but it's impossible, ze. Because of Mister Human's merciless mass extermination, the previous home got destroyed, ze...
Stop wasting your energy on useless chatter, easy!Yu...Maricha ish at her limit thoo..Yuu...Marisa, what's that..?Dunno, ze...Wanna shtop mwovin' outch... Wanna gwo back to our old Mishter Home...Yuu...Yu?Nho moaaar! It'sh cwold! Mishter Feet feel cwooold!Re-myu is gwoing back hooome!!Yuyu!? Don't cry little one! Get inside mommy's mouth and be warm-warm!