Red velvet cake alternative

I was thinking of making a red velvet cake today for Valentine's day, but my two year old is sensitive to red food coloring (it makes her skin blister!), so all the artificial coloring in the recipes I've seen makes me quite scared. I was wondering if someone either has an alternative red cake that uses something red to color it (tomatoes, cherries, etc.) or if anyone has tried to make red velvet cake and colored it with something natural...beet juice comes to mind. Any ideas?