It should be getting better not worse?

my 13 month old has always been attached to me. He was born 5 weeks early, only weighing 4lbs and he had stomach problems so I use to rock him and sing to him a lot when he was in a lot of pain. Any way he's a big boy now and healthy as can be. The problem is that when I'm at home, he doesn't want anything to do with anyone else but me. He was getting use to my husband around 8 months and was doing great, but recently he has started to get back in him old ways and not wanting anyone else to hold him. Yesterday my husband had the day off and stayed home with him while I went to work, so his grandmother who is his baby sitter got the day off. When I got home I went outside and they were on the swing just looking as happy as can be. They were just having fun playing. As soon as my son saw me, he started fussing and reaching out to me, so I got him and kissed him hello. He turned into a whole different person towards my husband. cont...