Speaking after wudu

Whoever does wudu for prayer, there is nothing wrong with him speaking permissible words with his family or brothers etc. It is not haram for him to speak certain words because of his wudu, rather what is haram before wudu is also haram afterwards, such as lying, backbiting, slandering, swearing, insulting etc. 

But because wudu is an expiation for bad deeds, and sins are erased by it, you should try to avoid haram things after doing it, so that you may stand before Allah pure and clean. Muslim (244) narrated from Abu Hurayrah that the Messenger of Allah (peace and blessings of Allah be upon him) said: “When the Muslim or believing slave does wudu and washes his face, every wrong thing that he looked at with his eyes comes out from his face with the water or with the last drop of water. When he washes his hands, every wrong thing that he did with his hands comes out from his hands with the water or with the last drop of water. When he washes his feet every wrong thing that he walked to with his feet comes out from his feet with the water or with the last drop of water, until he emerges cleansed of sin.” 

And he also narrated (245) from ‘Uthmaan ibn ‘Affaan that the Messenger of Allah (peace and blessings of Allah be upon him) said: “Whoever does wudu and does wudu well, his sins will emerge from his body until they even come out from beneath his fingernails.” 

And Allah knows best.