Congrats on getting your second! It's been 7 months since my second arrived. Be very prepared for some big time jealousy. My advice is to keep them mostly separated at first and only slowly integrate their time together, only when monitored. Slow n steady, best way to go
Scottie hated Casie at first. It took him some time to accept her, be comfortable with her, and then to play with her...over the span of a few months. Just be patient. You
could be lucky and it's love at first sight - not unheard of. If not, don't fret, with time they'll grow into it!