The Sport has 4 carry positions:
Newborn - Lying flat on a firm padded mattress is the best position for baby and healthy growth. Baby can face forward or backward facing Mom or Dad.
Toddler - Upright seat enables views of everything going on, also with a layback for resting times.
Toddler and Baby - Toddler on top and second newborn lying comfortable, flat and secure.
Two Toddlers - Both riding in line so you can go anywhere a single can. When the older toddler outgrows the need for the buggy simply return it back to a single.