double stroller recommendation

Bonnie

im looking for a double stroller for my little ones. my son will be 1 August 23rd and im expecting in januray. my sister has a really nice stroller from britax it has 2 seats one on top and one on bottom but also has an attacthment for a infant seat on top but i cant seem to find it anywhere. can anyone give me other recommendations. i love the stroller my sister has but I cant find anything like it.