Baby and dog

I have a 5 month old baby girl and a 4 year old shih tzu/ chihuahua and my dog shows no interest of even knowing her or wanting to be around her my husband was holding her the other day and as soon as I got her our dog jumps on him and starts rubbing himself on him marking his scent and I didn’t realize it until now but I feel like he won’t hurt her but I’m also cautious I’ve tried to see how he reacts to her beside him and he shys away or tries to move I don’t force it , I want him to do it on his own with our supervision and I want them to get along before we had her he was our baby he was spoiled and now I feel like he’s jealous of her. Any advice ?