Here is a graph showing the correlation between Serena Williams and Tennis. As you can see, the search for Wiliams pretty much rises and falls along with the search for tennis. Starting in April of 2017, the searches fro Seran slowly begin to drop, due to her maternity leave. In May of 2018 is where you see her start to spike up again, marking her return to the courts. In September of 2015, both Serena and tennis have a dramatic spike, because of the US Open in which Williams lost in the finals to Roberta Vinci. Another spike in September of 2018 signifies Serena's loss to Naomi Osaka in the US Open finals.
Here you see the relation between Serena Williams and Wimbledon, the oldest tennis tournament in the world. This graph shows the searches from the last 5 years, which is why you only see 5 major spikes in both categories, because the tournament only happens once a year. Every year the search for WIlliams goes up with Wimbledon. As you can see in 2017, there were much fewer searches for Serena because she did not compete in the tournament due to her maternity leave.
In the graph you see the correlaton between Serena Williams, and all Grand Slam tournaments which are the US Open, Australian Open, Wimbledon, and French Open. These major tournaments occur in late August- early September, January, July, and late May- early June. The major spikes in the searches for Williams all happen at these times, showing that she competed in these tournaments. From April to May, her searches decrease greatly while she was pregnant and on maternity leave.