[1] Beattie represented a combined Ireland under her maiden name of Catherine McMillen and won the singles gold medal at the Atlantic Bowls Championships.

[2] She also represented Northern Ireland during the 2014 Commonwealth Games before she was married.

[3] McMillen lost in the bronze medal play off in the singles at the 2014 Commonwealth Games to Colleen Piketh.

In 2015 she won the singles gold medal at the Atlantic Bowls Championships.

[4] In 2017, she won three medals at the European Bowls Championships[5] and one year later was selected as part of the Northern Ireland team for the 2018 Commonwealth Games on the Gold Coast in Queensland.