Impurities on clothing and furniture

Q: I would like to ask about some issues related to manhood. I am a healthy young man, married and father of kids. My issue is that when I'm aroused while sitting, resting or talking with my wife my penis secretes a liquid that's like oil. It is just a drop or two and that happens all the time when we are in good mood and I am at home with my family. I have absolutely no control to stop it. So is this liquid najis? Does my Wudhu and Ghusal break? If I had a wudhu can I pray while that drop on my undergarment is still wet? Can I pray in the same clothes once it is dry?

Q: If a baby throws up on me or my clothes, can I still pray in those clothes or are the clothes napaak? Also, if a baby urinates on me or my clothes, do I or my clothes become napaak? Lastly, if the blood of another person touches me or my clothes, am I or the clothes napaak?

Q: I have a question which always brings doubt to me with regards to ghusal. This happens to me all the time like this morning when I got back home from fajr I went to use the bathroom and on taking out my underpants I found a tiny dot of wetness and small white marks on my underwear. I then urinated and whilst urine emitted I watched to see if anything odd is emitted, I found that a little of white liquid came out as well which was sticky. Is this mani or mazi? I always get confused and then get waswasas. Do I have to make ghusal or do I just put on clean underpants and make wudhu?

Q: If there is napaaki on multiple spots on the wall, can I just use one cloth and wipe them all off the wall generally or would the napaaki spread all over?

Q: Yesterday my husband sat on a bench at the airport which had crumbs on it. I am not sure what the source of the crumbs are and I am now concerned that everywhere he sat thereafter like the car as well as the bags which came into contact with the parts of his clothes that touched the bench have now become napaak. I did check his clothes for traces of crumbs but it was hard to determine what was crumbs or just fluff and dirt and also what was the source of it as he was wearing the clothes the entire day and could have gotten the crumbs and dirt from various sources. Please let me know if I am required to wash everything that his clothes came into contact with thrice to make it paak?

Q: If there is dry najasat-e-ghalizah on a wall, will wiping it down once suffice? Also if clean dry clothes were placed on something that had the dry najasat-e-ghalizah on it, will they become napaak?

Q: If there is napaaki (due to sexual reasons) discharge on multiple places on the same wall, can I use one cloth and wipe it off all at the same time and reweipe with new cloths for the 2 other times or do I have to use cloth in that area wash it and redo 3 times for each of the little places?

Q: Please can you assist me with the following: My family eat non-meat products from non halaal restaurants such as fish, vegetables etc. I am therefore concerned that their clothes become napaak as a result of 1.) crumbs from their food falling onto their clothes (which could potentially be contaminated) or 2.) from sitting at such places as there is always a possibility of crumbs of the non halal food being on the seats. Whenever I see crumbs on their clothes I begin to get concerned however I am not certain if the crumbs are from eating at a non halal place or from eating elsewhere. I would therefore like to know if this makes everywhere they sit subsequent to eating at such places e.g. couch, bed, car etc napaak and would I have to wash it thrice every time this happens? Furthermore since I am not certain regarding the source of the crumbs, do I also need to was their clothes thrice.

Q: Can you explain to me how to clean off napaak discharge off many places on the walls with tissues?

Q: My son did urine on the bed and it got dry afterwards. If I sit on that bed then will me and my clothes be impure? If I wash the bedsheets only once,  if I touch the bed sheet wet or dry will I be impure in both cases?