Missing condom

So my boyfriend of 4 years we have a child together. Had a box with 4 condoms in it that we used for a short time after we had our child. We haven't touched them in over a year. Last week I peaked in the box and there was 4, but today I looked and there was only 3. I asked him about it and he denies taking 1, but there's no one else who could've taken it. He has to be lying right... condoms don't just disappear🙄