Infant chest thumps with dad in shared 'heartbeat'

In a video, her father, Josh Trimble, shows 7-month-old Opal -- who is battling acute flaccid myelitis -- that he?s always with her and that they ?share a heartbeat? by thumping his chest. Opal responds by thumping her chest too. The Oklahoma Blood Institute shard the family?s video on Facebook.?