Racial Remark about our baby's name?

We finally, after much deliberation between both my husband and I decided upon a baby name that we loved. Ella Rose. Ella after my great-grandma and my husband who's middle name is Ellis and my middle name that is Roseann. I realize that Ella is becoming increasingly popular, but My mother-in-law called last night to ask me where I got that name from? Then proceeded to tell me that name reminded her of a Fat-Black woman and that I needed to go back to the drawing board. I'm offended obviously,about the racial remark and because we had a hard time compromising for a name. What do I say to that?