Twin girls Jenna and Jillian Thistle-Thwaite were born 45 seconds apart, and when the doctors held them close to each other, they clasped hands. The twins were mono-amniotic, meaning they shared an amniotic sac. Now they're 2 years old and still close. Their mom says if one twin is crying, the other will find a way to comfort her. If their dad goes to the store and takes one of the twins with him, they both get upset and ask for each other.