Toddlers and soda

My mil gave my 2 yr old soda today. She doesn't drink soda ever. She does this often with junk food which we rarely allow our daughter to have and she knows this. My husband thinks I'm over reacting and said she wanted it because my niece had some. My niece is 4 and just had 6 teeth pulled and replaced with silver ones plus other fillings because of how they feed her. Her brother is 2 with 2 silver teeth same reason. I dont want her fed like them. What age did your toddlers have soda and would you be annoyed at this.