In Hindi, mota/moti means fat. Hindi is a language with gender, so mota is used to decribe fat masculine people or things, and moti is used to describe fat feminine people or things. I know Hindi better than Gujarati, so a lot of my language info comes from that even though it's not actually the language F's family speaks most of the time. It is, however, the language of Bollywood movies.
In Gujarati, mota and moti still mean fat. F's mom thinks I will get moti because I like sweets so much. I probably will, too, because every time I meet new people they feed me. I had two and a half lunches yesterday. But the same words also can be used for respect purposes. For instance, in Baghban a Gujarati guy calls Amitabh Bachchan "mota bhai" (bhai means brother) even though he is very fit for an old guy.
The reason I'm telling you all this is that F has his own mom and dad, but he also has aunts and uncles that he calls Mummy and Papa, too. Some of them are called Hisname-Papa and Hername-Mummy, but F's dad's oldest brother and his wife are called Mota Papa and Moti Mummy. Mota Papa is kind of like the family's Godfather, but without all the crime.
Anyway, when I was with F's family visiting aunts and uncles yesterday, Mota Papa called to say hi. I talked to him for a little bit and then he asked for F's mom, so I handed the phone off. She asked who it was, and I said "Moti Papa." This got huge laughs from everybody else in the room. Oops. Everyone is happy that I am learning Gujarati though, so they think my mistakes are cute. Thank god.