Wa'alaikumassalam sis! Okay, jangan risau sangat dulu, since you've already asked the doc and dia kata boleh hilang dengan sendiri bila anak grow older, that's actually good news! But honestly, if you're still worried or kalau benjolan tu nampak makin besar/berubah, better to follow up dengan doc again just to be sure, pediatrician boleh monitor and give you peace of mind. Few of us mum friends pun selalu panggil clinic balik kalau ada yang tak sure, it's completely normal and they don't mind!