Although they divorced in 1960, the 10 years of accompanying Leonard to different places for his career gave Mary the opportunity to meet and work with many influential psychologists including John Bowlby, as well as the occasion when they moved to Kampala, Uganda where her first "mother-infant" observation was done.
Selvom de blev skilt i 1960, gav, de 10 års ledsagelse af Leonard til forskellige steder til fordel for hans karriere, Mary mulighed for at møde og arbejde med mange indflydelsesrige psykologer, herunder John Bowlby, samt lejlighed til, da de flyttede til Kampala, Uganda, at hendes første "mor-barn" observation blev gjort.