2019 NCSA Junior Championships (Orlando, Florida)
In Orlando, Stadden had a loaded schedule, swimming a whopping 10 individual events. Her finals finishes included 1st in the 100 back (51.23), 1st in the 200 back (1:50.46), 2nd in the 50 back (24.53), 3rd in the 100 IM (54.43), 18th in the 100 free (50.14), 7th in the 50 breast (28.28), 7th in the 50 fly (24.30), and 14th in the 200 IM (2:02.37).
2018 Summer Nationals (Irvine, California)
In Irvine, Stadden placed 3rd in the 200 back (2:08.24), earning her a spot on the 2018 Jr Pan Pac team as well as the 2019 Pan American Games team. She also tied for 5th in the 50 back (28.13) and placed 9th in the 100 back (1:00.07).
2018 Jr Pan Pacific Championships (Suva, Fiji)
In Fiji, Stadden took gold in the 200 back (2:09.52) after setting a meet record in prelims (2:08.81).
2019 Pan American Games (Lima, Peru)
Stadden was the runner-up in the 200 backstroke (2:08.39), finishing 0.09 seconds behind fellow American Alexandra Walsh. Stadden went on to win gold in the 4×100 medley relay, leading off the prelims relay in a time of 1:00.29. The relay won gold in finals.
She also recorded a lifetime best of 59.69 on the leadoff 100 back leg of the mixed medley relay. The time made her the eighth fastest American female ever in the 17-18 age group for the 100 back.