Mothers and babies can instantly synchronize their hearts just by smiling at each other

This is an amazing study! In the analysis -

Mothers and their 3-month old infants were observed during face-to-face interactions while cardiac output was collected from mother and child. Micro-analysis of the partners' behavior marked episodes of gaze, affect, and vocal synchrony. Time-series analysis showed that mother and infant coordinate heart rhythms within lags of less than 1 s.

The verdict is out for dads! No study is been made for dads. I'm sure they will find that the Dads have more impact on the heart rate of young men that come to date their daughter on the first date!!!