Question:
Can a MATZEVA for a parent be put up during the 3 weeks/ 9 days?
Answer:
It is permitted to put up a mateiva for a parent during the 3 weeks or the nine days, however it is better not to do it on rosh chodosh if there will be hespedim or if they will say tehilliim then.
Sources:
Hadras Kodesh in the name of Dvar Yosef, see NItei Gavriel Aveilus 68 ftnt 19, MinchasYitzchok 3-52.
