Once the baby is born, we should wear clothes with lots of pockets
After the baby is born lets wear clothes with lots of pocket
子供が生まれたら - Once/after child is born, baby is born
Childよりbabyの方が使います
ポケットはそのままpocket
ポケットが多い - lots of pockets, many pockets
服 - clothes
着けましょう - lets wear clothes, should wear clothes
Once the baby is born, we should wear clothes with lots of pockets
After the baby is born, lets wear clothes with lots of pockets
When you have a baby, you should wear clothes that have lots of pockets.
この場合、次のような言い方ができますよ。
ーWhen you have a baby, you should wear clothes that have lots of pockets, so you can put things that your baby picks up in your pockets.
「赤ちゃんが生まれたら、赤ちゃんが拾ってしまうような物を入れられるよう、たくさんポケットのついた服を着た方がいいよ」
clothes that have lots of pockets で「たくさんポケットのついた服」と言えます。
ご参考まで！
イギリス 
カナダ 
