Despite this tragedy, Hubert’s widow along with their four children, decided to continue the expansion that was planned before Hubert’s death. Construction began in 1950 and a new brewing hall was ready for use in 1952 which is still in use during the winter months today. Of Hubert’s four sons, his oldest son Paul went to work at the brewery. His brother André joined him in 1958 after he finished his military service. The start of Paul’s political career came in 1958 after being elected mayor of Kobbegem. The demands of his political career would later compel him to sell his shares in the brewery completely. Though the De Keersmaeker Pils beer ballooned to 60% of the overall production by 1960, its popularity eventually fell, and by 1972 André was back to producing just lambic.
In [[Books#Geuze_.26_Kriek:_The_Secret_of_Lambic_Beern|''Geuze & Kriek: The Secret of Lambic'']], Van den Steen, “the Mort Subite named appeared two years previously in 1970, when a well-known Brussels café and geuze blending business A la Mort Subite was taken over from the Vossen brothers”, some of which was purchased from the [[Brasserie De Keersmaeker | De Keersmaeker]] brewery. Eventually, [[Brasserie De Keersmaeker | De Keersmaeker ]] took over the name and the Geuze Den Hert became Geuze Mort Subite. Mort Subite made its appearance in Belgium and France, and as early as 1984 in the United States.<ref name=GeuzeKriek>Jef Van den Steen, [[Books#Geuze & Kriek: The Secret of Lambic Beer|Geuze & Kriek: The Secret of Lambic Beer]], 2012</ref>
In 1985 , [[Brasserie De Keersmaeker | De Keersmaeker ]] hired a new brewer, Bruno Reinders, who was only twenty years old at the time. By 1989, [[Brasserie De Keersmaeker | De Keersmaeker]]r was looking to acquire other breweries. De Keersmaeker , and eventually acquired [[Brasserie Eylenbosch|Eylenbosch]] in Schepdaal , not for brewing, but for storage. Additionally in 1989, Paul De Keersmaeker sold his half of the brewery to the Alken-Maes group. At this point, overall quality began to suffer and numerous infections plagued the brewery. To combat this a new production manager, Marcel Lebeau (previously of [[Brasserie_Belle_Vue|Belle Vue]]) was appointed.<ref name=GeuzeKriek>Jef Van den Steen, [[Books#Geuze & Kriek: The Secret of Lambic Beer|Geuze & Kriek: The Secret of Lambic Beer]], 2012</ref>
Lebeau ascertained that the problem was originating in the coolship which was too small and too deep, and that it could not handle the amount of wort being pumped into it. To combat this problem, he began to divide the batches in two and pump half into a steel tank which was filled with environmental air. When analysis showed that the batches pumped into the tank picked up as much wild yeast to initiate fermentation, the coolship was eventually retired all together.<ref name=GeuzeKriek>Jef Van den Steen, [[Books#Geuze & Kriek: The Secret of Lambic Beer|Geuze & Kriek: The Secret of Lambic Beer]], 2012</ref>
When the Alken-Maes group was taken over by Scottish & New Castle André decided it was time to sell his share in the brewery and move on. Thus, the [[Brasserie De Keersmaeker | De Keersmaeker]] name was out of the brewing business. When Marcel Lebeau moved on, Bruno Reinders moved into the production manager position and shepherded the Mort Subite through a renovation and revamping under Scottish & New Castle. The company invested more than ne million Euros in the brewery. In 2000, Mort Subite made the jump into sweetened lambic by introducing a sweetened kriek followed by a framboise and a peach lambic (made only for Canada<ref name=LambicLand>Tim Webb, Chris Pollard, Siobhan McGinn, [[Books#LambicLand: A Journey Round the Most Unusual Beers in the World|LambicLand: A Journey Round the Most Unusual Beers in the World]], 2010</ref>). By 2005 they had introduced the Mort Subite Xtreme line, a watered down young lambic/fruit juice concoction.<ref name=GeuzeKriek>Jef Van den Steen, [[Books#Geuze & Kriek: The Secret of Lambic Beer|Geuze & Kriek: The Secret of Lambic Beer]], 2012</ref>
In 2007, Mort Subite reinroduced the Oude Kriek again, followed by a new push for the Oude Geuze. In 2008 the Alken-Maes name was passed over to Heineken who continued the investment in the Mort Subite name with Bruno Reinders still at the helm of production. Currently, the Mort Subite Oude Geuze and Oude Kriek are bottled at [[Brouwerij_Boon|Boon]]. Mort Subite is also a member of [[HORAL]].<ref name=GeuzeKriek>Jef Van den Steen, [[Books#Geuze & Kriek: The Secret of Lambic Beer|Geuze & Kriek: The Secret of Lambic Beer]], 2012</ref> <ref name=HoralMortSubite>http://www.horal.be/vereniging/mort-subite-kobbegem Horal - Mort Subite (Dutch)</ref>