My 2 year and 4 months old grandson running a fever almoust103, and constantly urinating. could it be uti or maybe something else?

Fever +urination: Uti is a concern, as it is possible in this age group. Fever is always a concern and needs to be checked by a physician if other symptoms like frequent urination is present and no respiratory ones are (cough, runny nose, earaches, etc).

Needs a dr visit...: He's only 2, he needs to be taken to a dr, get a urine checked as well as a physical exam. A fever of 103 is a good reason to take him to the dr quickly.