Horse galloping inside my tummy

One night, when me and my twins were having fun in bed, one of them put her head on my tummy. Then she said:

(H): mommy, there's a sound of horse galloping inside your tummy?
(M): hmmm? Horse galloping? What is it like?
(H): tagadap, tagadap, tagadap...
(M): oh, that. It's not a horse, Has. It's my heart beating. Here, try to put year ear here (right on my chest). Hear that?
(H): with eyes beaming Yes....
(M): you have heart beating inside you, too. Here, let mommy hear yours (and I put my head on her little chest).
(H): Oh?
(M): you can try to listen to Rania's. Rania, here.... Hasna would like to listen to your heart beating. Put your head on Rania's chest..., yup, like that. Hear that?
(H): yup.
(M): now it's Rania's turn. Put your ear on Hasna's chest. Hear that? The sound like horse galloping?
(R): yup... Mommy have it too?
(M): of course. Now, listen to mommy's.

And then, we spent some minutes listening to that one thing that connect us all: the heartbeat.