Please answer the following question: Generate a question about the following movie plot: Benjamin has lost his wife and decides to start a new life. He finds a house that has a zoo on the property. His young daughter is delighted about the idea and he goes ahead and purchases it. His son, Dylan, on the other hand, is not happy about it and retreats away to his artwork.The zoo is in desperate need of renovation and so Benjamin sets about the work with the head keeper, Kelly, and the rest of the zoo staff. The staff become unhappy when they realize that the zoo is in financial trouble and that the zoo may need to be sold.Dylan meets a new friend, Lilly. She has a crush on him, but he is oblivious. Dylan is delighted when he tells her that they may be moving due to the potential sale of the zoo. Lilly is upset by this.Benjamin discovers that his late wife has left him some money, and that he must 'follow his heart' in spending it. He decides to put the money into saving the zoo. The zoo staff are delighted, but Dylan is angry at the prospect of staying. He argues with his father.The next day they make-up and Dylan confesses that he misses Lily. His father advises him to reconcile with her. Dylan decides to tell Lily that he loves her.The day of the zoo's grand opening arrives, but is threatened by a huge rainstorm. Luckily they escape this, but still no visitors arrive. It turns out a tree has blocked people from gaining access to the zoo, so they think it isn't open.Kelly, the head keeper, confesses that she has feelings for Benjamin. They kiss and she suggests that they do the same again on New Year's Eve. He says he is looking forward to New Year.Benjamin takes his children to where his first met their mother.
A:
What is the zoo's grand opening threatened by?