请教wetting and filling diapers?

请教wetting and filling diapers是什么意思？

Sister had apointabout the new baby being a stink bug. While she couldn’t do much, she sure was good atwetting and filling diapers.
小熊妹妹说小宝宝是只小臭虫是有道理的。小宝宝自己干不了什么，肯定会常常尿湿自己，要换尿片。