Raibow baby names

I am waiting for a Dr appointment to tell me everything has passed after my first miscarriage. I was talking to my husband (who isn't as eager as I am to try for a rainbow) and I asked how he would feel if we used the Navajo word for "rainbow" as a name for a nickname until the baby arrives and maybe even the middle name because he's part Navajo. He just looked at me weird.

Naats'iilid : rainbow

Shaa' : sunshine

Shiko' : my fire

Sin : song

Those are my personal choices. My hubby likes the last three