What should I do with Libby and Bailey so they get along?

My oldest dog Lucy just passed away on saturday she was 10 and a half years old..And we have another dog Libby who is 8 years old she has had Lucy around all her life! And now that Lucy is gone she seamed very lonely so we got her a new puppy friend Bailey who is 8 weeks old, Libby came with us when we picked up Bailey and Libby seamed fine they did there sniffing and everything and they were both wagging there tails. When we brought them home it was nothing like that ! Libby wont go near Bailey and every time Bailey tries to go and play Libby growls at her to go away. What should we do so they get along? Did we make a mistake by getting a puppy to soon? Please help that would be great !