Tuhia he haere tonu mo tenei pene - I whanau a Halliday i te 19 o Akuhata 1926 i Liverpool ki a William Reginald Halliday me Edith Hilda (née Macneile Dixon). Ko tana hitori o te whanau he maha nga tupuna i mahi i te waahi rongoa. I kura a Halliday i te Kura o Dauntsey, i ako ia i te rongoa i te Whare Wananga o Glasgow i puta ai ia i te 1949. I te tau 1950 i mahi ia i tana ratonga motu i reira i mahi ai ia mo te waahanga hinengaro o te ope taua o Ingarangi. I mahi a Halliday i runga i te ahupūngao o te wiri o te maihao, e āhua ana he pānga ki te moe. He nui te uara o tana rangahau i te mea i etahi wa ka moe nga kaiurungi o Ingarangi i te wa e rere ana i te karaka mo te waka rererangi o Berlin
He aha? I kite a Arnold Carmichael, te tumuaki o te tari neurophysiology o te National Hospital. I akiaki a Carmichael i a Halliday kia haere mai ki te mahi ki te National i te wa i mutu ai tana mahi a motu i te tau 1953. I te tuatahi ka uru atu a Halliday ki tetahi roopu rangahau, i te tau 1961 ka noho ia hei kaitohutohu mo te neurophysiology haumanu ka noho hei upoko mo tana ake Kaunihera Rangahau Hauora.