Forgot My Sister's Gift

So today I did this thing that was so me. I had planned to surprise my younger sister with her birthday present but ended up forgetting it at home when we went out for ice cream. Instead of owning up, I lied and said the store ran out. Now every time she asks if I can go back, I have to remember where I left the toy on my bed, and it's getting old fast. Maybe honesty is overrated? Or am I just too lazy?