The Sims 3 Mermadic Kelp Lifetime Reward
Lifetime Happiness Points: 25,000
This LTR can save you from finding and befriending a Mermaid in order to turn your Sim into one instantly, which does save some time. Ultimately, it's a little costly for something that can be done fairly easily if you follow the Guide. There are better Lifetime Rewards out there. Once your Sim has befriended a Mermaid (70%), they need only ask about fish parts while underwater to get some free Kelp and accomplish the same.
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