most baba nyonya families will have at least 1 malay ancestor(on the female side), i read the book by prof Khoo Kay Kim (a famous historian and a true baba nyonya/peranakan), he mentioned in his book that he have a female malay ancestor when his forefather came to Malaya long long time ago and marry a local malay lady, and his family have record of every generation and passed down to future generations so he get to know about it, and he also mentioned for almost all peranakan families during that time also similar to his forefather married local malay lady because during that time they cannot bring women over to Malaya, and then after some time when things got better then only the later generations have money to bring over women from china and marry them or marry those chinese who just set foot in Malaya during that time

and thus the peranakan culture developed when the 1st gen of the forefathers of peranakans came from china and marry local malays, if those forefathers didnt marry local malay ladies, then the mix of chinese and malay culture will not develop