Ally’s space is difficult terrain

.@JeremyECrawford based on the phrase, "space of…creature is always difficult terrain" does it mean an ally's space should be difficult?

— B Lynn (@DaddyDM) August 31, 2015

Yes, an ally's space is difficult terrain for you. https://t.co/w778HWq1TM

— Jeremy Crawford (@JeremyECrawford) August 31, 2015