To know if you have a monkey problem (also referred to as simian infestation syndrome) you should look for telltale signs.
1) Monkeys need to eat. What do monkeys eat? Quite a variety of foods will suffice. A long standing favorite is fresh baguette from the bakery. Half eaten baguette is a dead giveaway. Here is a monkey caught in the act:
This being said, new research indicates that Penaten brand Zinc Oxide cream is quite tasty. If you find your brand new cream opened and half empty, you may have a problem. (More on this later)
2) Noises. Monkeys are very territorial and possessive. Often unexpected changes in environment (such as the lady of the household going downstairs to do the laundry) result in excessively loud wailing and stomping noises. Our motion sensitive cameras detected one such occurrence and caught this image of an upset, naked individual:
3) Tracks. Monkeys have been known to leave little monkey hand prints all over the house, especially after they've gotten whacky on diaper cream (see 1.)
4) Monkey sightings. First hand sightings are the most conclusive evidence of simian infestation. If you see a monkey, such as this one, be careful. This specimen has obviously had a little too much cream to eat, and is likely to be uncontrollably whacko. Cuteness and cuddles can also occur.
(Rebecca came into my room and woke me up this morning looking like this, needless to say I was surprised, as neither Madeleine nor I were aware that she could let herself out of her room when the door was closed. Poison control said not to worry about the cream that she ate.)