Looking for the name of a comic series about two wandering brothers

Question

In my childhood I read a short series of comics about;

• Two young brothers, forced to wander around wartime Europe(?) because they had no papers/identification.
• Common themes were difficulties with the authorities, and constantly having to flee or move on,
• The story stayed light-hearted and humorous, with the brothers typically prevailing against their oppressors,
• The style was similar to an Asterix or Tintin comic, possibly a French or Belgian artist?
• I think there were at least four books - not sure if more existed.

Some plot points or scenes I remember;

• They'd had a home with a big workshop, but were forced to leave,
• The older brother was an inventor, who built many solutions to their problems,
• At the end of each book they'd often have to flee offscreen to escape an angry crowd;
  • In one book they built a surprise hot air balloon and flew away,
  • In one book they followed a series of tunnels deeper and deeper underground,
  • In one book they built a few steps, then kept dismantling and rebuilding each step higher until they were high in the sky. (floating somehow?)
• At one point they had to go around a fortified country border extending out into the ocean.
• At one point they were stuck between two countries, about to go to war over a broken bridge - the elder brother fixed the bridge and moved on.
• At one point they were so sick of the bureaucrats denying them access or requiring papers they didn't have, that they built a 'fence making machine' that built tidy wrought iron fences around every government building.

I have NO idea of the name of the series or the author. I read it probably in the early to mid 1990s.

Answer 1

Some of this sounds like The House that Beebo built, written by y Janine Ast & Alain Gree, illustrated by Philippe Fix. I've only read this one but I believe there is at least one other story. (Also I haven't read it for a while, so my memory may be fuzzy!)

Beebo inherits an old house which is neglected and overgrown. He and his friend Mop fix it up. One room is a large glass bubble where Mop blows bubbles out, there is a wooden staircase/bookcase inside. The city council decides to tear it down, (possibly for a new road?). One night Beebo and Mop refit a mechanical digger up as a dragon and scare the workers off so the council sends the police and fire department. They retreat up the house till they run out of room. Beebo builds 5-6 wooden stairs, sets them in the air and the pair climb aboard. They pull the last step up, continue the process and climb their way into the sky.

I don't remember if Beebo and Mop's relationship was stated - Mop looks young but I don't think they were father and son.

I would say this question fits here as this is a fantasy book.

edit: found a lovely picture: