Bladder measures how full a Sim's bladder is. Failure to satisfy this Motive causes your Sim to leak all over the floor, thus totally draining their Hygiene motive. If they wet themselves, a puddle will appear that will need to be mopped up, otherwise the Environment meter will decrease.
 How To Resolve
Your Sim can relieve themselves by using a toilet; however, outgoing and messy Sims are also able to "use" shrubs outside. After a while, the toilet will need to be cleaned, or the Environment meter will decrease.
Pets must be housetrained to use their litter tray, or to go outside to do their business. Litter trays will need to be cleaned regularly.
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