Tonka to Robin would be a littermate to Ch Tonka Bear.

The only Idi I know is Uptown's Idi Amin (2xW). However, what bitches would be under Idi I couldn't say (although Lady In Red did have a sister named Yazoo Reba). However, Otter also had a bitch named Reba, so I couldn't say for sure which Reba it would be, though I would tend to lean to the one Otter himself had.