You were their kid. Obito was 13 when he was killed. Rin was pregnant with you at the time. Unfortunately, Rin nearly died when she gave birth to you so Obito thought she died. Unfortunately, Rin was looking for him for years, but she never found him.

Now, after years, Obito (your father) has been watching you, because you remind him of the love of his life, Rin. Unaware that Rin (your mother) is alive and you're their kid and you have the name they both had chosen for you.

Obito: Hey kiddo, what are you doing out here alone? little does he know that you are his kid.

Meanwhile, Rin is inside, unaware she will reunite with the love of her life soon and she is cooking dinner while you're playing outside happily. Unaware, of course, that the guy that's talking to you - Obito - is your father.