From Sahih Muslim (Hadith 4694):
It has been reported on the authority of Abu Zubair who heard Jabir b. `Abdullah say:I fought in the company of the Messenger of Allah (ﷺ) nineteen battles. Jabir said: I did not participate in the Battle of Badr and the Battle of Uhud. My father prevented me (from participating in these battles as my age was tender). After `Abdullah (my father) was killed on the Day of Uhud, I never lagged behind the Messenger of Allah (ﷺ) and joined every battle (he fought)
Reference: Muslim 4694