Like redcrx has said, no two babies are the same, so you really shouldnt be comparing your two. It sounds like your little girl is good, shes just a typical 5 month old who still needs a night feed to get her through the night.
I believe that at this age, they will only wake if they are hungry or thirsty, so only wake for a good reason. If she sleeps well after her night feed, you really are quite lucky as some babies will wake foe a couple of feeds at night, even at 5 months. I still think the key here is to get into a night routine of waking around the same time every night.
Good luck :)